Capillary Impact on Tidal Response of Groundwater in Unconfined Aquifers With Finite Thickness, Anisotropy and Wellbore Storage-An Analytical Model

Zhang, Jiangwei1,2; Liang, Xiuyu1,3; Wang, Chi-Yuen4

2023-03-01

10.1029/2022WR033578

WATER RESOURCES RESEARCH   影响因子和分区

0043-1397

1944-7973

This study develops a novel, two-dimensional analytical model to study capillary effects on Earth tidal responses of groundwater in unconfined aquifers. It differs from the previous model by accounting for effects of finite aquifer thickness, anisotropy and wellbore storage. We test the present model against the previous model and numerical simulations and apply it to the field data. Several significant results are obtained: (a) At high conductivity K > 10(-5)m/s), the effect of capillary zones dominates tidal responses of groundwater and causes higher amplitude ratio and smaller phase shift compared with that predicted by the unconfined aquifer model without a capillary zone. At low conductivity (K < 10(-5) m/s), the effect of capillary zones on the tidal responses diminishes. (b) The impact of the finite thickness on the tidal response is regulated by the anisotropy. If the anisotropic ratio is small ( K-z/K< 1 ), the impact of thickness may be negligible; at high anisotropic ratio ( K-z/K > 1 ), however, the amplitude ratio decreases and the phase shift increases, and the response differs substantially from that of the previous model, which is caused by a change in the flow pattern. (c) Wellbore storage have significant impacts on the tidal response at low conductivity (K ,< 10 (-5) m/s) but negligible impact at higher conductivity. (d) The present model marginally improved the fit by the half-space model to the field data from a well in SW China, showing that the remaining misfit to the field data by models with capillarity cannot be due to finite aquifer thickness, anisotropy, or wellbore storage.

unsaturated flow two-dimensional analytical solution tidal response finite aquifer thickness

SCI ; EI

英语

第一 ; 通讯

National Natural Science Foundation of China[41977165] ; Natural Science Foundation of Shenzhen[20220814221815001] ; Shenzhen Key Laboratory of Natural Gas Hydrates[ZDSYS20200421111201738]

Environmental Sciences & Ecology ; Marine & Freshwater Biology ; Water Resources

Environmental Sciences ; Limnology ; Water Resources

WOS:000973565400001

AMER GEOPHYSICAL UNION

20231613905161

Anisotropy ; Aquifers ; Boreholes ; Digital storage ; Flow patterns ; Geometry ; Groundwater flow ; Groundwater resources ; Hydrogeology ; Oil field equipment

Groundwater:444.2 ; Geology:481.1 ; Oil Field Equipment:511.2 ; Fluid Flow, General:631.1 ; Data Storage, Equipment and Techniques:722.1 ; Mathematics:921 ; Physical Properties of Gases, Liquids and Solids:931.2

ENVIRONMENT/ECOLOGY

Web of Science

1.Southern Univ Sci & Technol, Shenzhen Key Lab Nat Gas Hydrates, Shenzhen, Peoples R China
2.Univ Leeds, Sch Civil Engn, Leeds, England
3.Southern Univ Sci & Technol, Sch Environm Sci & Engn, Shenzhen, Peoples R China
4.Univ Calif Berkeley, Dept Earth & Planetary Sci, Berkeley, CA USA

Zhang, Jiangwei,Liang, Xiuyu,Wang, Chi-Yuen. Capillary Impact on Tidal Response of Groundwater in Unconfined Aquifers With Finite Thickness, Anisotropy and Wellbore Storage-An Analytical Model[J]. WATER RESOURCES RESEARCH,2023,59(3).

Zhang, Jiangwei,Liang, Xiuyu,&Wang, Chi-Yuen.(2023).Capillary Impact on Tidal Response of Groundwater in Unconfined Aquifers With Finite Thickness, Anisotropy and Wellbore Storage-An Analytical Model.WATER RESOURCES RESEARCH,59(3).

Zhang, Jiangwei,et al."Capillary Impact on Tidal Response of Groundwater in Unconfined Aquifers With Finite Thickness, Anisotropy and Wellbore Storage-An Analytical Model".WATER RESOURCES RESEARCH 59.3(2023).